Projectors are generally devices that integrate light sources, optics systems, electronics, and displays for projecting images from computers or video devices onto walls or screens, for large-image viewing. They are especially popular among business users who give presentations as part of their job responsibilities. Newer projectors can weigh as little as a few pounds, making them well suited for business travelers. As the quality of projection technology has improved, projectors are also finding their way into peoples' homes for high-definition television (HDTV) and other home entertainment applications.
The quality of the signals connected to a projection device can greatly vary between a “clean” signal and a “noisy” signal. Clean signals typically can be displayed without any “trash” appearing along the edges of the projected image; noisy signals, on the other hand, frequently have noise, or flicker, along one or more edges of the projected image.
Arbitrarily clipping of a portion of the picture has been used to address these noisy edges. Unfortunately, this results in a loss of a portion of the picture, even if it is not necessary.